A collection of cell wall deficient, Gram variable, pleomorphic organisms has been collected from cases of endocarditis, urethrtis, fever of undetermined origin, brain abscess, and other deep abscesses. Two strains of this collection have recently reverted to definitive parent forms, both of which are Streptococcus sanguis. This data is being prepared for publication. The strains have been well documented through ultrastructure, guanine-cytosine base ratios, acrylamide gel protein patterns, fatty acid profiles via gas liquid chromatography, morphological and biochemical characteristics.